Method and apparatus for sharpening saw blades

ABSTRACT

Method and apparatus for orienting saw blades cutting teeth wherein all correspondingly oriented lateral cutting surfaces of teeth that are abraded and/or brazed are congruently oriented with respect to any plane perpendicular to the axis of rotation of the blade body, essentially independently of any waviness in the blade body. Laterally floating clamps on opposite sides of the blade body operate to sense the location of that body and releasably clamp the body essentially without disturbing waviness. Abrading is carried out at essentially the same relative orientation during each successive abrading operating, while the blade is gripped.

United States Patent 1 1 Allison June 12, 1973 METHOD AND APPARATUS FORSHARPENING SAW BLADES [75] Inventor: Rudolph L. Allison, Rockford, Ill.

[22] Filed: Sept. 24, 1971 [21] Appl. No.: 186,520

76/34, 46, 47, 47 A, 78, 79, 8 D, 40, 4'1, 42, 43, 44, 45,47 B,48;51/112, 225

[56] References Cited UNITED STATES PATENTS 1,045,052 11 1912 McLean etal 76/48 R 2,638,018 5 1953 Davis et a1. 76/37 R Gill 76/40 R 3,295,3961/1967 Kolb 76/25 R 3,034,378 5/1962 Anderson 76/112 R 2,770,930 11/1956Norman 51/225 R Primary Examiner-Harrison L. l-linson Attorney-James E.Cockfield [57] ABSTRACT Method and apparatus for orienting saw bladescutting teeth wherein all correspondingly oriented lateral cuttingsurfaces of teeth that are abraded and/or brazed are congruentlyoriented with respect to any plane perpendicular to the axis of rotationof the blade body, essentially independently of any waviness in theblade body. Laterally floating clamps on opposite sides of the bladebody operate to sense the location of that body and releasably clamp thebody essentially without disturbing waviness. Abrading is carried out atessentially the same relative orientation during each successiveabrading operating, while the blade is gripped.

5 Claims, 4 Drawing Figures INVENTOR RUDOLPH L. ALLISON ATTORNEYS 4METHOD AND APPARATUS FOR SHARPENING SAW BLADES BACKGROUND OF THEINVENTION This invention relates to a method and apparatus for providingproperly oriented cutting faces of saw blade cutting teeth.- Moreparticularly this invention relates to such a method and apparatuswherein the abrading of such cutting faces or even the initialpositioning of such faces is accomplished essentially independently ofany waviness that may exist in the blade body.

During the use of circular saw blades, particularly carbide tippedblades employed in cutting steel bar stock, the problem of blade life(i.e. the frequency with which the cutting teeth have to be resharpenedor with which the blade need be replaced) is particularly acute. In thepast attempts directed toward increasing blade life have been made.

These attempts have involved a practice denominated as hammering.According to this practice, the blade body which carries the cuttingteeth is tensioned to impart a proper amount of stiffness thereto whileat the same time providing a true running tool with minimal run out. Inthis connection a 0.004 inch run out (i.e. amount of lateral waviness inthe blade body as it is rotated about its cutting axis) has beenconsidered generally acceptable.

As will be appreciated, it had generally been considered that in theabsence of an essentially true running blade body, the waviness in theblade body would cause significant chatter as the corresponding lateralcutting faces of the successive teeth sequentially entered the cuttingzone at different lateral locations relative to the bounding workpieceportions on opposite sides of the cut. Thus, by reason of the waviness,sequentially entering cutting teeth would be physically pressed fromside to side as they were forced to enter the cut. The resulting chatterand wear greatly contributed to a reduction in blade life.

According to the present invention, the significance of hammering toenhance true running of the tool can be reduced. Moreover, the problemsof waviness of the blade body as they bear upon blade life can beminimized or eliminated. This is accomplished by taking steps to insurethat all correspondingly oriented lateral cutting surfaces of successiveteeth are essentially identically oriented with respect to a planeperpendicular to the axis of rotation of the blade body. In'thisfashion, the relative location between each corresponding-cutting toothand the workpiece remains essentially the same independently of anywaviness in the blade body.

As hereinafter more fully described, the essentially identicalorientation of the corresponding cutting surfaces is realized byaltering the position of clamping means that hold the blade bodyduring-sequential operations such as grinding, that effect theorientation. These operations are then all performed in connection witheach tooth relative to the same plane perpendicular to the axis ofrotation of the blade body.

Clamp means have been-previously employed to hold the blade body duringgrinding operations sequentially performed in connection with successivecutting surfaces. However, once the clamp means were set for a grindingoperation ona tooth surface, the clamp means remained identically setfor the successive grinding operations in connection with similarlypositioned tooth surfaces. All these grinding operations were thenperformed at the same location, that location being determined relativeto the basically fixed position clamping means.

It will be appreciated that such a technique may increase rather thanreduce the chatter and wear problem earlier discussed. If the blade bodyhas any waviness, this waviness is disturbed during grinding operationssince the clamping means is in the same position after the blade isindexed for each grinding operation. In other words, the fixed positionof the clamping means functions to press the waviness out of the indexedblade body. Each grinding operation then irisures only thatcorresponding cutting surfaces are identically oriented with respect tothe clamping means at the time of grinding. Thus, these surfaces arenonuniforrnly oriented with respect to a plane perpendicular to the axisof blade rotation when the blade is permitted to spring back to arelaxed position after it is removed from the clamping zone. Since theblade is utilized in this relaxed position wherein waviness is basicallyreturned to the blade, the chatter and wear problem is present tocontribute to a reduction in blade life.

During a conference prior to the time of conception of the presentinvention, it was suggested by another that a blade body might beclamped during a grinding operation by laterally floating clamp meansthat would not disturb waviness of that body. This suggestion was nothowever, accompanied by a specific suggestion that the use of floatingclamp means could be coupled with performance of each grinding operationat the same location relative to the same plane perpendicular to theaxis of rotation of the blade body.

The present invention is directed to an improvement wherein eachsuccessive grinding operation is so performed. In this fashion, it maybe insured that all correspondingly positioned lateral cutting, surfacesof successive teeth are essentially identically oriented with respect tothe same plane during use. The independence of this orientation from anywaviness in the blade body aids in enhancing blade life since the teethbasically follow one another into the cutting zone in the same locationrelative to the workpiece.

OBJECTS AND SUMMARY OF PREFERRED FORMS OF THE INVENTION Recognizing theneed for improved blade life and that the importance of the presence orabsence of an essentially true running blade body can be minimized whilestill enhancing the conforming entry of successive teeth of a circularsaw blade into a cutting zone, and further recognizing that the use offloating clamp means without disturbing the waviness of the blade bodycan be combined with the performance, relative to the same planeperpendicular to the blade body axis of rotation, of operations thateffect the orientation of corresponding cutting surfaces, it is ageneral object of the invention to provide an improved method andapparatus for orienting such cutting surfaces.

It is a particular object of the invention to provide such an improvedmethod and apparatus wherein each successive abrading operationassociated with corresponding cutting surfaces of indexed teeth isperformed basically identically relative the same plane perpendicular tothe axis of rotation, while the blade body is held by floating clampmeans without disturbing any waviness in the blade body.

A preferred method of the present invention entails a method of abradinglateral surfaces of carbide cutting teeth inserts of a rotary saw bladeincluding the steps of: clamping or gripping the body of the saw blade,essentially without disturbing any waviness of the body, betweenlaterally floating clamp means on opposite sides of the body, whichclamp means operate to sense the location of the blade body and clamp itin that location; abrading one of said lateral surfaces of a cuttingtooth with the saw blade, body clamped by the clamp means; releasing theclamp means from the saw blade body; rotatably indexing the saw blade toa position for subsequent abrading of a correspondingly positionedlateral surface of a successive cutting tooth; repeating the clampingstep with laterally floating clamp means on opposite sides of the body;and abrading the correspondingly positioned lateral surface. Accordingto the improvement of the present invention, each successive one of theabove abrading steps is performed at essentially the same locationrelative to the same plane perpendicular to the axis of rotation of theblade body. Thus, all correspondingly oriented lateral cutting surfacesthat are abraded are congruently oriented with respect to any planeperpendicular to the axis of rotation of the blade body.

A preferred apparatus of the invention entails apparatus for abradingthe lateral surfaces including: laterally floating clamp means disposedon opposite sides of the blade body for sensing the location of thatbody and releasably clamping it essentially without disturbing anywaviness; movable abrading means for abrading a lateral surface of acutting tooth with the body clamped; and indexing means for rotatablyindexing the blade to a position for abrading of a correspondinglypositioned lateral surface of a successive tooth. According to theimprovement of the present invention, advancing means are provided foradvancing the abrading means of the above combination to essentially thesame abrading locations relative to the same plane perpendicular to theaxis of rotation of the blade body, during each successive abradingoperation.

Other objects and advantages of the present invention will becomeapparent from the following detailed description of preferred forms ofthe present invention, with reference to the accompanying drawings inwhich like numerals refer to like elements, and in which;

THE DRAWINGS FIG. 1 is a side elevational view depicting apparatusaccording to the improvement of the present invention;

FIG. 2 is a partial top plan view of the apparatus of FIG. 1;

FIG. 3 is a schematic illustration depicting the principles of theimprovement according to the present invention; and

FIG. 4 is a partially schematic illustration ofa sensing and clamp meansutilizable with the improvement according to the present invention.

DETAILED DESCRIPTION With reference to FIGS. 1 and 2, an apparatus forpracticing the improvement of the present invention will be described.The illustrated apparatus may be employed for abrading lateral cuttingsurfaces of cutting teeth of a rotary saw blade 10. The blade is of thetype which includes carbide cutting teeth inserts 12 circumferentiallyspaced about the outer periphery of the blade body 14. The schematicshowing of the blade 10 with the inserts 12 is intended to represent anegative angle blade, the configuration of which is well known.

As indicated at 16, a suitable mounting is provided for supporting theblade for rotation about an axis indicated at 18. If desired, themounting may be essentially identical to that employed when the blade ismounted for use in a cutting operation. For example, the mounting maytake the form of that disclosed in US. Pat. application Ser. No. 47,830filed June 9, 1970 by Willy J. Goellner for Carbide Saw Blade LockingDevice, and assigned to the assignee of the present invention. Thedisclosure of that application is hereby incorporated by reference.

Suitable means is provided for rotating the mounting means 16 along withthe blade 10 about the axis 18. This means preferably takes the form ofan indexing means 19 for sequentially rotating the mounting means 16 andblade 10 by a desired angular extent, i.e., one equal to thecircumferential spacing between the carbide inserts 12. Any suitablemotor means may suffice for this purpose.

Adjacent the blade 10, a support assembly 20 may be provided. Thissupport assembly 20 is operative to support a grinding means assembly 22and two clamping means schematically shown at 24 and 26. The illustratedgrinding means assembly 22 includes a grinding head 28 suitably attachedto a saddle 30. The saddle 30 is slidably mounted for reciprocalmovement on generally parallel ways 32 located on the upper portion ofthe support assembly 20. As will be apparent, legs of the saddle 30 areslidably received for translation on the ways 32 toward and away fromthe blade 10, and these Ieg's may cooperate with stop means 36 on theways 32 to limit the feed of the grinding means assembly 22 toward theaxis 18 of blade rotation. Similar stop means 37 may be employed tolimit the travel of the saddle 30 away from the axis of rotation 18.

Feeding of the grinding means assembly may be accomplished in anysuitable manner. For example, a threaded driving rod 38 may be suitablysecured to the saddle 30. One end of the threaded rod 38 may threadedlyengage with the internal threaded periphery of a split nut 40. The nut40 may be mounted for rotation by means of the output shaft 42 of asuitable reversible motor 44 mounted on the support member 20. Suitablelimit switches may be associated with the stops 36 and 38 for preventingthe rotation of the nut 40 by the motor 44 after the saddle 22 reachesits limit positions. As will be apparent, rotation of the nut 40 inopposite directions would be operative to translate the saddle 30 inopposite directions through the threaded cooperation with the rod 38. Ofcourse, suitable provision is made to accomodate the length of thethreaded rod 38 during saddle retraction to the stop means 37.

Rotatably mounted on the grinding head 28 is a grinding wheel 46. Thegrinding wheel may be rotatably driven by suitable motor means indicatedschematically at 48 in FIG. 2 but omitted from FIG. 1 for clarity ofillustration.

The previously noted clamp means 24 and 26 are respectively supported onthe support assembly or table 20 on opposite sides of the blade body 14.These clamping means 24 and 26 cooperate to clamp the blade body 14 inposition during a grinding operation as depicted in FIG. 1. Ashereinafter more fully described in connection with FIG. 4, thisclamping opera- FIGS. 1 and 2, the mounting of the clamping means 24 and26 is such as to not interfere with operation of the grinding wheel 46or with indexing rotation of the saw blade 10. Any suitable arrangementmay be employed to provide such a mounting. For example, the supportassembly may include a stepped shelf portion 50 disposed on one side ofthe mounted blade 10. One of the clamping means 26 may be mounted onthis support shelf 50 as indicated at 52. A mounting comprised of offsetbracket arms 53 and 54 ultimately supported on the table 50 as indicatedat 55 may be employed to dispose the other clamp means 24 on the otherside of the mounted blade body 14. The clamp means 24 and 26 are thussupported in generally oppositely facing aligned relationship onopposite sides of the blade body.

In operation according to the present invention, the clamps 24 and 26are employed to grip or clamp the body 14 of the saw blade essentiallywithout disturbing any waviness of the body, adjacent the cuttingsurface to be abraded. The grinding wheel 46 of the grinding meansassembly 22 is then employed to abrade a lateral surface of the carbidecutting tooth insert 12 appropriately positioned in relatiOn to thegrinding assembly 22. A grinding operation entails feeding of the saddle22 through appropriate means (such as the rotatable nut 40 cooperatingwith the threaded rod 38), and rotation of the grinding wheel 46. Asdepicted in FIG. 1, the feeding may take place in a plane generallyperpendicular to the axis of rotation 18 of the blade 10.

After performance of the abrading operation associated with one of thecarbide inserts 12, the clamp means 24 and 26 are released from theblade body 14. Thebody 14 is thereafter indexed to bring the nextsuccessive tooth into position for a subsequent abrading operation. Anessentially identical abrading operation from the standpoint oforientation with respect to a plane perpendicular to the axis ofrotation 18 of the blade 14 is then carried out. In other words, themeans provided for feeding or advancing the abrading means assembly 22is operative to so advance that assembly to essentially the sameabrading locations relative to the same plane perpendicular to the axisof rotation of the blade body, during each successive abradingoperation.

Through the performance of each of the successive abrading steps atessentially the same location relative to the same plane perpendicularto the axis of rotation of the blade body, and with the blade body 14clamped without disturbing any waviness, all correspondingly orientedlateral cutting surfaces of successive teeth are essentially identicallyoriented with respect to any plane perpendicular to the blade rotationaxis 18. Thus, during a cutting operation with the blade 10, therelative location between each corresponding lateral cutting surfacesand the workpiece remains essentially the same independently of anywaviness in the blade body.

From the foregoing, it will be appreciated that the present invention isconcerned with orientation of lateral cutting surfaces of cutting teethof a rotatable saw blade. In this connection, it may be noted that allof the foregoing discussion in connection with FIGS. 1 and 2 wasdirected to such faces disposed on one side of the blade body.Symmetrical faces are located on the opposite side of the blade body.Moreover, as will be recognized by those skilled in the art, eachcarbide insert 12 may be comprised of a primary tooth and a secondarytooth including a plurality of lateral cutting faces, and the presentinvention may be employed in connection with abrading operationsassociated therewith.

If desired, the grinding head 28 coupled to the saddle 30 may besuitably mounted for reorientation relative to that saddle 30 dependingon the configuration and intended orientation of the tooth surface to beabraded. Similarly, provision may be made for adjusting the direction offeed of a grinding assembly in practicing the present invention.However, in any event, the abrading face of the grinding tool itself isoperated in the same abrading location for all teeth after theappropriate depth and orientation of the grinding assembly is set forany side grind, i.e., a grind associated with a lateral cutting surface.

With reference to FIG. 3, further aspects of the improvement accordingto the present invention may be understood. In FIG. 3, a flat plan of ablade 10 is schematically depicted. The blade body 14 has, asillustrated, a degree of waviness which would result in run out of theblade during use. However, the clamping means 24 and 26 are operated inconnection with each grinding operation to avoid disturbing the wavinessin the blade body 14. This may be accomplished by employing the clampingmeans to sense the location of the blade body and then to clamp theblade at essentially that precise location.

The grinding assembly 22 including the grinding wheel 46 is illustratedschematically in FIG. 3. The arrangement of FIG. 3 is illustrative of anangular orientation of the grinding wheel 46 employed in connection withgrinding of a lateral cutting surface 56 that lies in a plane at anangle with respect to planes perpendicular to the axis of rotation ofthe blade 10. It will be readily apparent that through practice of thepresent invention the laterally outermost portions of the face 56 wouldbe all located in the same plane as indicated by the lines 58, after thesuccessive indexing and grinding operations are performed. At the sametime, the angle of inclination with respect to planes perpendicular tothe axis of blade rotation would be identical for each surface 56, i.e.,the teeth would be congruently oriented.

With reference now to FIG. 4, a suitable arrangement for insuring thatthe clamp means is operational without disturbing the waviness of theblade body may be seen. The clamp means 24 may include an aperturedbearing member or sleeve schematically shown at 60. This sleeve may befixedly mounted with respect to the shelf 50 of the support assembly andslidably receives a hollow stem 62. One end of the stem remote from theblade body 14 may be appropriately threaded, as indicated at 64, tocooperate with a drive gear 66. The drive gear 66 may be suitablymounted for rotation by means of a suitable reversible motor 68. It willbe apparent that rotation of the motor 68 in opposite directions isoperative to translate the stem 62 within the bearing sleeve 60 towardand away from the blade body 14.

The hollow stem 62 may receive a sensing member or rod 70' that normallyaxially projects therebeyond toward the blade body 14. The sensing rod70 may be biased to its projecting position by means of a spring 72within the stem 62 acting on a collar 74 integral with the sensing rod70.

As the illustrated stem 62 is translated toward the blade body throughappropriate rotation of the drive gear 66 by means of the motor 68, thesensing rod 70 will engage the blade body 14 and be caused to moverearwardly relative to the stem 62 against the bias of the spring 72.Upon completion of this rearward movement, the sensing rod 70 cooperateswith a microswitch 74 so as to halt advancing movement of the stem 62,in a manner which will become apparent. Appropriate dimensionalrelationships and delays associated with halting of advancing movementplace the front surface 61 of the rod 62 at the blade body l4.-The gearand thread drive arrangement is such that, upon such halting, the stem62 functions as a fixed clamp against the blade body. However,essentially no distortion of any waviness in the blade body would beintroduced. A similar clamping stem associated with the other clampingmeans 26 may be employed to engage the opposite side of the blade body14 to complete the clamping operation.

Prior to indexing for subsequent grinding operations, the clamping stem62 is retracted through reverse rotation of the motor 68. During thisretraction, a suitable shoulder 76 projecting from the body of theclamping stem 62 may cooperate with a suitable limit microswitch 78.When the projection 76 actuates microswitch 78, retracting movement ofthe clamping stem 62 is halted.

As may be seen in FIG. 4, the motor 68 may be driven by suitable ACpower source 79. One lead from the power source is illustrated as beingprovided with switch means 80 that is operative to cause reversingmovement of the motor 68. In the illustrated position, the switch means80 is in a condition to enable current flow to the motor 68 through thecontact 82 and the limit switch 78, with the current flow being such asto cause retracting movement of the clamping stem 62. However, the limitmicro-switch 78 will be moved to an open position by the shoulder 76 soas to cut off such current flow, thereby stopping the retractingmovement of the clamping stem 62, when the stem 62 reaches the fullreverse position.

In this position, the micro-switch 74 carried by the clamping stem 62 isin its biased closed, i.e., not actuated, position insofar as thesensing rod 70 is biased to its outer projecting position. Thiscondition of that micro-switch 74 is operative to enable advancingmovement of the stem 62 upon appropriate passing of current to the motor68 when the reversing switch 80 is conditioned with respect to the othercontact 84.

After the blade body 14 is properly indexed, the reversing switch 80 isso conditioned by an operator. Thus, the clamping stem 62 is advancedalong with the sensing rod 70 carried thereby. After suitable depressionof the sensing rod 70 resulting from engagement with the blade body 14,the micro-switch 74 is actuated to halt advancing movement by cuttingoff current flow to the motor 68.

Reverse movement causing retraction of the clamping stem 62 isaccomplished by reversing the condition of the reversing switch 80 tothe illustrated position so as to pass current to the motor 68 throughthe biased closed limit micro-switch 78 until that switch is actuated asabove discussed. At this time, retraction is completed, and themicro-switch 74 closes again since the sensor rod 70 is biased to itsouter position.

It will be appreciated that the second clamping means 26 may beidentical-to the sensing and clamping means 24 discussed in connectionwith FIG. 4. Alternatively, with the one clamping means functioning as asensing means to be appropriately located adjacent the blade body 14,the other clamping means 26 need only be advanced to clampinglycooperate with the first clamping means 24 without the need for anysensing arrangement. It will also be apparent that other clampingarrangements for avoiding disturbance of any waviness of the blade body14 may be employed.

The foregoing description of the improvement according to the presentinvention has been made specifically in connection with grindingoperations. It will, however, be appreciated that the principles of theinvention may be applied in connection with any other operationaffecting the orientation of the lateral cutting surfaces, such as whenthe carbide inserts 12 are braised in position. This positioning, ofcourse, results in an initial orientation of the lateral cutting facesrelative to a plane perpendicular to the axis of rotation of the blade.Through clamping the blade in position without disturbing the wavinessof the body and through performing the orienting operation (e.g. thebrazing of the tips in position) in an identical fashion with respect toa plane perpendicular to the axis of blade rotation, the presentinvention may be practiced in such initial positioning operations. Inthis fashion, the amount of side grinding to be subsequently performedmay be significantly reduced.

It may be here noted that through practice of the present invention, itmay be possible to minimize or eliminate the need for dubbing of acarbide insert tip. Dubbing constitutes a grinding operation associatedwith the vertical side edge of each tooth in a plane parallel to thesurface of the blade body. Such grinding is intended to eliminate thesharp edge so as to enable the blade to tend to track itself through thecut.

It will also be recognized that the present invention is not limited tocarbide tipped saw blade operations although it finds particular utilityand advantages therein. Abrading operations associated with lateralcutting surfaces of any movable saw blade may be practiced according tothe present invention.

Although the invention has been described in connection with preferredforms thereof, it will be appreciated by those skilled in the art thatadditions, substitutions, modifications, and deletions may be madewithout departing from the spirit and scope of the invention as definedin the appended claims.

What is claimed is:

1. In a method of abrading lateral cutting surfaces of cutting teeth ofa rotary saw blade including the steps of: gripping the saw blade, priorto abrading of one lateral surface, between clamp means on oppositesides of the blade body, with the gripping step comprising sensing thelocation of the blade body and clamping the body in the locationessentially without disturbing any existing waviness thereof; abradingthe one lateral surface with abrading means while the blade is gripped;releasing the saw blade from the grip of the clamp means; indexing thesaw blade for subsequent abrading of a correspondingly oriented lateralsurface; and repeating the steps of gripping, releasing and abrading inconnection with that correspondingly oriented lateral surface; theimprovement comprising:

performing each of the abrading steps with the abrading means operatingat the same operating position relative to the same plane perpendicularto the axis .of rotation of the blade body, whereby all correspondinglyoriented lateral cutting surfaces that are abraded are congruentlyoriented with respect to any plane perpendicular to the axis of rotationof the blade body, essentially independently of any waviness in theblade body.

2. In a method of performing an operation effecting orientation of thelateral cutting surfaces of cutting teeth of a rotary saw bladeincluding the steps of: gripping the saw blade, prior to performing theorienting operation in connection with one of the lateral surfaces,between clamp means on opposite sides of the blade body, with thegripping step comprising sensing the location of the blade body andclamping the body in the location essentially without disturbing anyexisting waviness thereof; performing the orientation effectingoperation while the blade is gripped; releasing the saw blade from thegrip of the clamp means; indexing the saw blade for a subsequent one ofsaid operations in connection with a correspondingly oriented lateralsurface; and repeating the steps of gripping, releasing and performingthe orientation operation in connection with that correspondinglyoriented lateralsurface; the improvement comprising:

performing each of said orientation effecting operations at the sameoperating position relative to the same plane perpendicular to the axisof rotation of the blade body, whereby the laterally outermost portionsof each of said lateral surfaces lie in a common plane.

3. The improvement according to claim 2 wherein the steps of performingsaid orientation effecting operations comprise abrading the lateralsurfaces.

4. The improvement according to claim 2 wherein the cutting teethcomprise inserts and wherein the steps of performing said orientationeffecting operations comprise brazing the inserts in position on theblade body.

5. In an apparatus for abrading lateral cutting teeth of a rotary sawblade including: laterally floating clamp means on opposite sides of theblade body for sensing the location of that body and releasably clampingsaid body essentially without disturbing any waviness; movable abradingmeans for abrading a lateral cutting surface with the body clamped; andindexing means for rotatably indexing the blade to a position forabrading of correspondingly positioned lateral surfaces of successiveteeth; the improvement comprising:

advancing means for advancing said abrading means to essentially thesame abrading locations relative to the same plane perpendicular to theaxis of rotation of the blade body, during each successive abradingoperation.

3, 738, 201 Dated June 12, 1973 Patent No.

Inventor(s) Rudolph L. Allison It is certified that error appears in theabove-identified patent and that said Letters Patent are herebycorrected as shown below:

In the heading, line 21, change 186, 520- to "183, 520".

Signed and sealed this 16th day of April 197M.

(SEAL) Attest:

G4a MARSHALL DANN EDWARD l'IOFLETCHERJR.

Commissioner of Patents Attesting Officer USCOMM-DC 6037 6-P69 FORMPO-105O (10-69) u.s. oovznnmzm PRINTING ornc: 2 was o-ssa-au,

1. In a method of abrading lateral cutting surfaces of cutting teeth ofa rotary Saw blade including the steps of: gripping the saw blade, priorto abrading of one lateral surface, between clamp means on oppositesides of the blade body, with the gripping step comprising sensing thelocation of the blade body and clamping the body in the locationessentially without disturbing any existing waviness thereof; abradingthe one lateral surface with abrading means while the blade is gripped;releasing the saw blade from the grip of the clamp means; indexing thesaw blade for subsequent abrading of a correspondingly oriented lateralsurface; and repeating the steps of gripping, releasing and abrading inconnection with that correspondingly oriented lateral surface; theimprovement comprising: performing each of the abrading steps with theabrading means operating at the same operating position relative to thesame plane perpendicular to the axis of rotation of the blade body,whereby all correspondingly oriented lateral cutting surfaces that areabraded are congruently oriented with respect to any plane perpendicularto the axis of rotation of the blade body, essentially independently ofany waviness in the blade body.
 2. In a method of performing anoperation effecting orientation of the lateral cutting surfaces ofcutting teeth of a rotary saw blade including the steps of: gripping thesaw blade, prior to performing the orienting operation in connectionwith one of the lateral surfaces, between clamp means on opposite sidesof the blade body, with the gripping step comprising sensing thelocation of the blade body and clamping the body in the locationessentially without disturbing any existing waviness thereof; performingthe orientation effecting operation while the blade is gripped;releasing the saw blade from the grip of the clamp means; indexing thesaw blade for a subsequent one of said operations in connection with acorrespondingly oriented lateral surface; and repeating the steps ofgripping, releasing and performing the orientation operation inconnection with that correspondingly oriented lateral surface; theimprovement comprising: performing each of said orientation effectingoperations at the same operating position relative to the same planeperpendicular to the axis of rotation of the blade body, whereby thelaterally outermost portions of each of said lateral surfaces lie in acommon plane.
 3. The improvement according to claim 2 wherein the stepsof performing said orientation effecting operations comprise abradingthe lateral surfaces.
 4. The improvement according to claim 2 whereinthe cutting teeth comprise inserts and wherein the steps of performingsaid orientation effecting operations comprise brazing the inserts inposition on the blade body.
 5. In an apparatus for abrading lateralcutting teeth of a rotary saw blade including: laterally floating clampmeans on opposite sides of the blade body for sensing the location ofthat body and releasably clamping said body essentially withoutdisturbing any waviness; movable abrading means for abrading a lateralcutting surface with the body clamped; and indexing means for rotatablyindexing the blade to a position for abrading of correspondinglypositioned lateral surfaces of successive teeth; the improvementcomprising: advancing means for advancing said abrading means toessentially the same abrading locations relative to the same planeperpendicular to the axis of rotation of the blade body, during eachsuccessive abrading operation.